低温下单壁碳纳米管拉曼光谱温度效应研究

The Study of Temperature Dependence of Raman Spectra of Single-walled Carbon Nanotubes at Low Temperature

在单壁碳纳米管的低温拉曼光谱测量过程中,发现径向呼吸模(RBM)和正切拉伸模(GM)的拉曼频移在低温下的温度效应和在高温时的温度效应存在着很大的区别,在低温下拉曼光谱的频移和温度并不呈线性关系。而且,在温度为210K时,单壁碳纳米管内部的振动结构可能发生了变化。在低温下单壁碳纳米管拉曼峰的强度的变化是不可逆的。

The cryogenic Raman spectra of the single- walled carbon nanotubes（SWNTs）are measured at 632.8nm laser excitation wavelength. The results indicate that the temperature dependence of RBM and GM at low temperature is greatly different from that at high temperature. At low temperature, frequencies of Raman spectra are not a linear relation with temperature. The inner structure of SWNTs is likely to have a variety when the temperature is 210K. The intensity of Raman spectra are not reversible at low temperature.